1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Donn Seeley at Berkeley Software Design, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #ifndef lint 36 static const char copyright[] = 37 "@(#) Copyright (c) 1991, 1993\n\ 38 The Regents of the University of California. All rights reserved.\n"; 39 #endif /* not lint */ 40 41 #ifndef lint 42 #if 0 43 static char sccsid[] = "@(#)init.c 8.1 (Berkeley) 7/15/93"; 44 #endif 45 static const char rcsid[] = 46 "$FreeBSD$"; 47 #endif /* not lint */ 48 49 #include <sys/param.h> 50 #include <sys/boottrace.h> 51 #include <sys/ioctl.h> 52 #include <sys/mman.h> 53 #include <sys/mount.h> 54 #include <sys/reboot.h> 55 #include <sys/stat.h> 56 #include <sys/sysctl.h> 57 #include <sys/uio.h> 58 #include <sys/wait.h> 59 60 #include <db.h> 61 #include <err.h> 62 #include <errno.h> 63 #include <fcntl.h> 64 #include <kenv.h> 65 #include <libutil.h> 66 #include <paths.h> 67 #include <signal.h> 68 #include <stdarg.h> 69 #include <stdbool.h> 70 #include <stdio.h> 71 #include <stdlib.h> 72 #include <string.h> 73 #include <syslog.h> 74 #include <time.h> 75 #include <ttyent.h> 76 #include <unistd.h> 77 78 #ifdef SECURE 79 #include <pwd.h> 80 #endif 81 82 #ifdef LOGIN_CAP 83 #include <login_cap.h> 84 #endif 85 86 #include "mntopts.h" 87 #include "pathnames.h" 88 89 /* 90 * Sleep times; used to prevent thrashing. 91 */ 92 #define GETTY_SPACING 5 /* N secs minimum getty spacing */ 93 #define GETTY_SLEEP 30 /* sleep N secs after spacing problem */ 94 #define GETTY_NSPACE 3 /* max. spacing count to bring reaction */ 95 #define WINDOW_WAIT 3 /* wait N secs after starting window */ 96 #define STALL_TIMEOUT 30 /* wait N secs after warning */ 97 #define DEATH_WATCH 10 /* wait N secs for procs to die */ 98 #define DEATH_SCRIPT 120 /* wait for 2min for /etc/rc.shutdown */ 99 #define RESOURCE_RC "daemon" 100 #define RESOURCE_WINDOW "default" 101 #define RESOURCE_GETTY "default" 102 103 static void handle(sig_t, ...); 104 static void delset(sigset_t *, ...); 105 106 static void stall(const char *, ...) __printflike(1, 2); 107 static void warning(const char *, ...) __printflike(1, 2); 108 static void emergency(const char *, ...) __printflike(1, 2); 109 static void disaster(int); 110 static void revoke_ttys(void); 111 static int runshutdown(void); 112 static char *strk(char *); 113 static void runfinal(void); 114 115 /* 116 * We really need a recursive typedef... 117 * The following at least guarantees that the return type of (*state_t)() 118 * is sufficiently wide to hold a function pointer. 119 */ 120 typedef long (*state_func_t)(void); 121 typedef state_func_t (*state_t)(void); 122 123 static state_func_t single_user(void); 124 static state_func_t runcom(void); 125 static state_func_t read_ttys(void); 126 static state_func_t multi_user(void); 127 static state_func_t clean_ttys(void); 128 static state_func_t catatonia(void); 129 static state_func_t death(void); 130 static state_func_t death_single(void); 131 static state_func_t reroot(void); 132 static state_func_t reroot_phase_two(void); 133 134 static state_func_t run_script(const char *); 135 136 static enum { AUTOBOOT, FASTBOOT } runcom_mode = AUTOBOOT; 137 #define FALSE 0 138 #define TRUE 1 139 140 static int Reboot = FALSE; 141 static int howto = RB_AUTOBOOT; 142 143 static int devfs; 144 static char *init_path_argv0; 145 146 static void transition(state_t); 147 static state_t requested_transition; 148 static state_t current_state = death_single; 149 150 static void execute_script(char *argv[]); 151 static void open_console(void); 152 static const char *get_shell(void); 153 static void replace_init(char *path); 154 static void write_stderr(const char *message); 155 156 typedef struct init_session { 157 pid_t se_process; /* controlling process */ 158 time_t se_started; /* used to avoid thrashing */ 159 int se_flags; /* status of session */ 160 #define SE_SHUTDOWN 0x1 /* session won't be restarted */ 161 #define SE_PRESENT 0x2 /* session is in /etc/ttys */ 162 #define SE_IFEXISTS 0x4 /* session defined as "onifexists" */ 163 #define SE_IFCONSOLE 0x8 /* session defined as "onifconsole" */ 164 int se_nspace; /* spacing count */ 165 char *se_device; /* filename of port */ 166 char *se_getty; /* what to run on that port */ 167 char *se_getty_argv_space; /* pre-parsed argument array space */ 168 char **se_getty_argv; /* pre-parsed argument array */ 169 char *se_window; /* window system (started only once) */ 170 char *se_window_argv_space; /* pre-parsed argument array space */ 171 char **se_window_argv; /* pre-parsed argument array */ 172 char *se_type; /* default terminal type */ 173 struct init_session *se_prev; 174 struct init_session *se_next; 175 } session_t; 176 177 static void free_session(session_t *); 178 static session_t *new_session(session_t *, struct ttyent *); 179 static session_t *sessions; 180 181 static char **construct_argv(char *); 182 static void start_window_system(session_t *); 183 static void collect_child(pid_t); 184 static pid_t start_getty(session_t *); 185 static void transition_handler(int); 186 static void alrm_handler(int); 187 static void setsecuritylevel(int); 188 static int getsecuritylevel(void); 189 static int setupargv(session_t *, struct ttyent *); 190 #ifdef LOGIN_CAP 191 static void setprocresources(const char *); 192 #endif 193 static int clang; 194 195 static int start_session_db(void); 196 static void add_session(session_t *); 197 static void del_session(session_t *); 198 static session_t *find_session(pid_t); 199 static DB *session_db; 200 201 /* 202 * The mother of all processes. 203 */ 204 int 205 main(int argc, char *argv[]) 206 { 207 state_t initial_transition = runcom; 208 char kenv_value[PATH_MAX]; 209 int c, error; 210 struct sigaction sa; 211 sigset_t mask; 212 213 /* Dispose of random users. */ 214 if (getuid() != 0) 215 errx(1, "%s", strerror(EPERM)); 216 217 BOOTTRACE("init(8) starting..."); 218 219 /* System V users like to reexec init. */ 220 if (getpid() != 1) { 221 #ifdef COMPAT_SYSV_INIT 222 /* So give them what they want */ 223 if (argc > 1) { 224 if (strlen(argv[1]) == 1) { 225 char runlevel = *argv[1]; 226 int sig; 227 228 switch (runlevel) { 229 case '0': /* halt + poweroff */ 230 sig = SIGUSR2; 231 break; 232 case '1': /* single-user */ 233 sig = SIGTERM; 234 break; 235 case '6': /* reboot */ 236 sig = SIGINT; 237 break; 238 case 'c': /* block further logins */ 239 sig = SIGTSTP; 240 break; 241 case 'q': /* rescan /etc/ttys */ 242 sig = SIGHUP; 243 break; 244 case 'r': /* remount root */ 245 sig = SIGEMT; 246 break; 247 default: 248 goto invalid; 249 } 250 kill(1, sig); 251 _exit(0); 252 } else 253 invalid: 254 errx(1, "invalid run-level ``%s''", argv[1]); 255 } else 256 #endif 257 errx(1, "already running"); 258 } 259 260 init_path_argv0 = strdup(argv[0]); 261 if (init_path_argv0 == NULL) 262 err(1, "strdup"); 263 264 /* 265 * Note that this does NOT open a file... 266 * Does 'init' deserve its own facility number? 267 */ 268 openlog("init", LOG_CONS, LOG_AUTH); 269 270 /* 271 * Create an initial session. 272 */ 273 if (setsid() < 0 && (errno != EPERM || getsid(0) != 1)) 274 warning("initial setsid() failed: %m"); 275 276 /* 277 * Establish an initial user so that programs running 278 * single user do not freak out and die (like passwd). 279 */ 280 if (setlogin("root") < 0) 281 warning("setlogin() failed: %m"); 282 283 /* 284 * This code assumes that we always get arguments through flags, 285 * never through bits set in some random machine register. 286 */ 287 while ((c = getopt(argc, argv, "dsfr")) != -1) 288 switch (c) { 289 case 'd': 290 devfs = 1; 291 break; 292 case 's': 293 initial_transition = single_user; 294 break; 295 case 'f': 296 runcom_mode = FASTBOOT; 297 break; 298 case 'r': 299 initial_transition = reroot_phase_two; 300 break; 301 default: 302 warning("unrecognized flag '-%c'", c); 303 break; 304 } 305 306 if (optind != argc) 307 warning("ignoring excess arguments"); 308 309 /* 310 * We catch or block signals rather than ignore them, 311 * so that they get reset on exec. 312 */ 313 handle(disaster, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, 314 SIGXCPU, SIGXFSZ, 0); 315 handle(transition_handler, SIGHUP, SIGINT, SIGEMT, SIGTERM, SIGTSTP, 316 SIGUSR1, SIGUSR2, SIGWINCH, 0); 317 handle(alrm_handler, SIGALRM, 0); 318 sigfillset(&mask); 319 delset(&mask, SIGABRT, SIGFPE, SIGILL, SIGSEGV, SIGBUS, SIGSYS, 320 SIGXCPU, SIGXFSZ, SIGHUP, SIGINT, SIGEMT, SIGTERM, SIGTSTP, 321 SIGALRM, SIGUSR1, SIGUSR2, SIGWINCH, 0); 322 sigprocmask(SIG_SETMASK, &mask, NULL); 323 sigemptyset(&sa.sa_mask); 324 sa.sa_flags = 0; 325 sa.sa_handler = SIG_IGN; 326 sigaction(SIGTTIN, &sa, NULL); 327 sigaction(SIGTTOU, &sa, NULL); 328 329 /* 330 * Paranoia. 331 */ 332 close(0); 333 close(1); 334 close(2); 335 336 if (kenv(KENV_GET, "init_exec", kenv_value, sizeof(kenv_value)) > 0) { 337 replace_init(kenv_value); 338 _exit(0); /* reboot */ 339 } 340 341 if (kenv(KENV_GET, "init_script", kenv_value, sizeof(kenv_value)) > 0) { 342 state_func_t next_transition; 343 344 if ((next_transition = run_script(kenv_value)) != NULL) 345 initial_transition = (state_t) next_transition; 346 } 347 348 if (kenv(KENV_GET, "init_chroot", kenv_value, sizeof(kenv_value)) > 0) { 349 if (chdir(kenv_value) != 0 || chroot(".") != 0) 350 warning("Can't chroot to %s: %m", kenv_value); 351 } 352 353 /* 354 * Additional check if devfs needs to be mounted: 355 * If "/" and "/dev" have the same device number, 356 * then it hasn't been mounted yet. 357 */ 358 if (!devfs) { 359 struct stat stst; 360 dev_t root_devno; 361 362 stat("/", &stst); 363 root_devno = stst.st_dev; 364 if (stat("/dev", &stst) != 0) 365 warning("Can't stat /dev: %m"); 366 else if (stst.st_dev == root_devno) 367 devfs++; 368 } 369 370 if (devfs) { 371 struct iovec iov[4]; 372 char *s; 373 int i; 374 375 char _fstype[] = "fstype"; 376 char _devfs[] = "devfs"; 377 char _fspath[] = "fspath"; 378 char _path_dev[]= _PATH_DEV; 379 380 iov[0].iov_base = _fstype; 381 iov[0].iov_len = sizeof(_fstype); 382 iov[1].iov_base = _devfs; 383 iov[1].iov_len = sizeof(_devfs); 384 iov[2].iov_base = _fspath; 385 iov[2].iov_len = sizeof(_fspath); 386 /* 387 * Try to avoid the trailing slash in _PATH_DEV. 388 * Be *very* defensive. 389 */ 390 s = strdup(_PATH_DEV); 391 if (s != NULL) { 392 i = strlen(s); 393 if (i > 0 && s[i - 1] == '/') 394 s[i - 1] = '\0'; 395 iov[3].iov_base = s; 396 iov[3].iov_len = strlen(s) + 1; 397 } else { 398 iov[3].iov_base = _path_dev; 399 iov[3].iov_len = sizeof(_path_dev); 400 } 401 nmount(iov, 4, 0); 402 if (s != NULL) 403 free(s); 404 } 405 406 if (initial_transition != reroot_phase_two) { 407 /* 408 * Unmount reroot leftovers. This runs after init(8) 409 * gets reexecuted after reroot_phase_two() is done. 410 */ 411 error = unmount(_PATH_REROOT, MNT_FORCE); 412 if (error != 0 && errno != EINVAL) 413 warning("Cannot unmount %s: %m", _PATH_REROOT); 414 } 415 416 /* 417 * Start the state machine. 418 */ 419 transition(initial_transition); 420 421 /* 422 * Should never reach here. 423 */ 424 return 1; 425 } 426 427 /* 428 * Associate a function with a signal handler. 429 */ 430 static void 431 handle(sig_t handler, ...) 432 { 433 int sig; 434 struct sigaction sa; 435 sigset_t mask_everything; 436 va_list ap; 437 va_start(ap, handler); 438 439 sa.sa_handler = handler; 440 sigfillset(&mask_everything); 441 442 while ((sig = va_arg(ap, int)) != 0) { 443 sa.sa_mask = mask_everything; 444 /* XXX SA_RESTART? */ 445 sa.sa_flags = sig == SIGCHLD ? SA_NOCLDSTOP : 0; 446 sigaction(sig, &sa, NULL); 447 } 448 va_end(ap); 449 } 450 451 /* 452 * Delete a set of signals from a mask. 453 */ 454 static void 455 delset(sigset_t *maskp, ...) 456 { 457 int sig; 458 va_list ap; 459 va_start(ap, maskp); 460 461 while ((sig = va_arg(ap, int)) != 0) 462 sigdelset(maskp, sig); 463 va_end(ap); 464 } 465 466 /* 467 * Log a message and sleep for a while (to give someone an opportunity 468 * to read it and to save log or hardcopy output if the problem is chronic). 469 * NB: should send a message to the session logger to avoid blocking. 470 */ 471 static void 472 stall(const char *message, ...) 473 { 474 va_list ap; 475 va_start(ap, message); 476 477 vsyslog(LOG_ALERT, message, ap); 478 va_end(ap); 479 sleep(STALL_TIMEOUT); 480 } 481 482 /* 483 * Like stall(), but doesn't sleep. 484 * If cpp had variadic macros, the two functions could be #defines for another. 485 * NB: should send a message to the session logger to avoid blocking. 486 */ 487 static void 488 warning(const char *message, ...) 489 { 490 va_list ap; 491 va_start(ap, message); 492 493 vsyslog(LOG_ALERT, message, ap); 494 va_end(ap); 495 } 496 497 /* 498 * Log an emergency message. 499 * NB: should send a message to the session logger to avoid blocking. 500 */ 501 static void 502 emergency(const char *message, ...) 503 { 504 va_list ap; 505 va_start(ap, message); 506 507 vsyslog(LOG_EMERG, message, ap); 508 va_end(ap); 509 } 510 511 /* 512 * Catch an unexpected signal. 513 */ 514 static void 515 disaster(int sig) 516 { 517 518 emergency("fatal signal: %s", 519 (unsigned)sig < NSIG ? sys_siglist[sig] : "unknown signal"); 520 521 sleep(STALL_TIMEOUT); 522 _exit(sig); /* reboot */ 523 } 524 525 /* 526 * Get the security level of the kernel. 527 */ 528 static int 529 getsecuritylevel(void) 530 { 531 #ifdef KERN_SECURELVL 532 int name[2], curlevel; 533 size_t len; 534 535 name[0] = CTL_KERN; 536 name[1] = KERN_SECURELVL; 537 len = sizeof curlevel; 538 if (sysctl(name, 2, &curlevel, &len, NULL, 0) == -1) { 539 emergency("cannot get kernel security level: %m"); 540 return (-1); 541 } 542 return (curlevel); 543 #else 544 return (-1); 545 #endif 546 } 547 548 /* 549 * Set the security level of the kernel. 550 */ 551 static void 552 setsecuritylevel(int newlevel) 553 { 554 #ifdef KERN_SECURELVL 555 int name[2], curlevel; 556 557 curlevel = getsecuritylevel(); 558 if (newlevel == curlevel) 559 return; 560 name[0] = CTL_KERN; 561 name[1] = KERN_SECURELVL; 562 if (sysctl(name, 2, NULL, NULL, &newlevel, sizeof newlevel) == -1) { 563 emergency( 564 "cannot change kernel security level from %d to %d: %m", 565 curlevel, newlevel); 566 return; 567 } 568 #ifdef SECURE 569 warning("kernel security level changed from %d to %d", 570 curlevel, newlevel); 571 #endif 572 #endif 573 } 574 575 /* 576 * Change states in the finite state machine. 577 * The initial state is passed as an argument. 578 */ 579 static void 580 transition(state_t s) 581 { 582 583 current_state = s; 584 for (;;) 585 current_state = (state_t) (*current_state)(); 586 } 587 588 /* 589 * Start a session and allocate a controlling terminal. 590 * Only called by children of init after forking. 591 */ 592 static void 593 open_console(void) 594 { 595 int fd; 596 597 /* 598 * Try to open /dev/console. Open the device with O_NONBLOCK to 599 * prevent potential blocking on a carrier. 600 */ 601 revoke(_PATH_CONSOLE); 602 if ((fd = open(_PATH_CONSOLE, O_RDWR | O_NONBLOCK)) != -1) { 603 (void)fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) & ~O_NONBLOCK); 604 if (login_tty(fd) == 0) 605 return; 606 close(fd); 607 } 608 609 /* No luck. Log output to file if possible. */ 610 if ((fd = open(_PATH_DEVNULL, O_RDWR)) == -1) { 611 stall("cannot open null device."); 612 _exit(1); 613 } 614 if (fd != STDIN_FILENO) { 615 dup2(fd, STDIN_FILENO); 616 close(fd); 617 } 618 fd = open(_PATH_INITLOG, O_WRONLY | O_APPEND | O_CREAT, 0644); 619 if (fd == -1) 620 dup2(STDIN_FILENO, STDOUT_FILENO); 621 else if (fd != STDOUT_FILENO) { 622 dup2(fd, STDOUT_FILENO); 623 close(fd); 624 } 625 dup2(STDOUT_FILENO, STDERR_FILENO); 626 } 627 628 static const char * 629 get_shell(void) 630 { 631 static char kenv_value[PATH_MAX]; 632 633 if (kenv(KENV_GET, "init_shell", kenv_value, sizeof(kenv_value)) > 0) 634 return kenv_value; 635 else 636 return _PATH_BSHELL; 637 } 638 639 static void 640 write_stderr(const char *message) 641 { 642 643 write(STDERR_FILENO, message, strlen(message)); 644 } 645 646 static int 647 read_file(const char *path, void **bufp, size_t *bufsizep) 648 { 649 struct stat sb; 650 size_t bufsize; 651 void *buf; 652 ssize_t nbytes; 653 int error, fd; 654 655 fd = open(path, O_RDONLY); 656 if (fd < 0) { 657 emergency("%s: %m", path); 658 return (-1); 659 } 660 661 error = fstat(fd, &sb); 662 if (error != 0) { 663 emergency("fstat: %m"); 664 close(fd); 665 return (error); 666 } 667 668 bufsize = sb.st_size; 669 buf = malloc(bufsize); 670 if (buf == NULL) { 671 emergency("malloc: %m"); 672 close(fd); 673 return (error); 674 } 675 676 nbytes = read(fd, buf, bufsize); 677 if (nbytes != (ssize_t)bufsize) { 678 emergency("read: %m"); 679 close(fd); 680 free(buf); 681 return (error); 682 } 683 684 error = close(fd); 685 if (error != 0) { 686 emergency("close: %m"); 687 free(buf); 688 return (error); 689 } 690 691 *bufp = buf; 692 *bufsizep = bufsize; 693 694 return (0); 695 } 696 697 static int 698 create_file(const char *path, const void *buf, size_t bufsize) 699 { 700 ssize_t nbytes; 701 int error, fd; 702 703 fd = open(path, O_WRONLY | O_CREAT | O_EXCL, 0700); 704 if (fd < 0) { 705 emergency("%s: %m", path); 706 return (-1); 707 } 708 709 nbytes = write(fd, buf, bufsize); 710 if (nbytes != (ssize_t)bufsize) { 711 emergency("write: %m"); 712 close(fd); 713 return (-1); 714 } 715 716 error = close(fd); 717 if (error != 0) { 718 emergency("close: %m"); 719 return (-1); 720 } 721 722 return (0); 723 } 724 725 static int 726 mount_tmpfs(const char *fspath) 727 { 728 struct iovec *iov; 729 char errmsg[255]; 730 int error, iovlen; 731 732 iov = NULL; 733 iovlen = 0; 734 memset(errmsg, 0, sizeof(errmsg)); 735 build_iovec(&iov, &iovlen, "fstype", 736 __DECONST(void *, "tmpfs"), (size_t)-1); 737 build_iovec(&iov, &iovlen, "fspath", 738 __DECONST(void *, fspath), (size_t)-1); 739 build_iovec(&iov, &iovlen, "errmsg", 740 errmsg, sizeof(errmsg)); 741 742 error = nmount(iov, iovlen, 0); 743 if (error != 0) { 744 if (*errmsg != '\0') { 745 emergency("cannot mount tmpfs on %s: %s: %m", 746 fspath, errmsg); 747 } else { 748 emergency("cannot mount tmpfs on %s: %m", 749 fspath); 750 } 751 return (error); 752 } 753 return (0); 754 } 755 756 static state_func_t 757 reroot(void) 758 { 759 void *buf; 760 size_t bufsize; 761 int error; 762 763 buf = NULL; 764 bufsize = 0; 765 766 revoke_ttys(); 767 runshutdown(); 768 769 /* 770 * Make sure nobody can interfere with our scheme. 771 * Ignore ESRCH, which can apparently happen when 772 * there are no processes to kill. 773 */ 774 error = kill(-1, SIGKILL); 775 if (error != 0 && errno != ESRCH) { 776 emergency("kill(2) failed: %m"); 777 goto out; 778 } 779 780 /* 781 * Copy the init binary into tmpfs, so that we can unmount 782 * the old rootfs without committing suicide. 783 */ 784 error = read_file(init_path_argv0, &buf, &bufsize); 785 if (error != 0) 786 goto out; 787 error = mount_tmpfs(_PATH_REROOT); 788 if (error != 0) 789 goto out; 790 error = create_file(_PATH_REROOT_INIT, buf, bufsize); 791 if (error != 0) 792 goto out; 793 794 /* 795 * Execute the temporary init. 796 */ 797 execl(_PATH_REROOT_INIT, _PATH_REROOT_INIT, "-r", NULL); 798 emergency("cannot exec %s: %m", _PATH_REROOT_INIT); 799 800 out: 801 emergency("reroot failed; going to single user mode"); 802 free(buf); 803 return (state_func_t) single_user; 804 } 805 806 static state_func_t 807 reroot_phase_two(void) 808 { 809 char init_path[PATH_MAX], *path, *path_component; 810 size_t init_path_len; 811 int nbytes, error; 812 813 /* 814 * Ask the kernel to mount the new rootfs. 815 */ 816 error = reboot(RB_REROOT); 817 if (error != 0) { 818 emergency("RB_REBOOT failed: %m"); 819 goto out; 820 } 821 822 /* 823 * Figure out where the destination init(8) binary is. Note that 824 * the path could be different than what we've started with. Use 825 * the value from kenv, if set, or the one from sysctl otherwise. 826 * The latter defaults to a hardcoded value, but can be overridden 827 * by a build time option. 828 */ 829 nbytes = kenv(KENV_GET, "init_path", init_path, sizeof(init_path)); 830 if (nbytes <= 0) { 831 init_path_len = sizeof(init_path); 832 error = sysctlbyname("kern.init_path", 833 init_path, &init_path_len, NULL, 0); 834 if (error != 0) { 835 emergency("failed to retrieve kern.init_path: %m"); 836 goto out; 837 } 838 } 839 840 /* 841 * Repeat the init search logic from sys/kern/init_path.c 842 */ 843 path_component = init_path; 844 while ((path = strsep(&path_component, ":")) != NULL) { 845 /* 846 * Execute init(8) from the new rootfs. 847 */ 848 execl(path, path, NULL); 849 } 850 emergency("cannot exec init from %s: %m", init_path); 851 852 out: 853 emergency("reroot failed; going to single user mode"); 854 return (state_func_t) single_user; 855 } 856 857 /* 858 * Bring the system up single user. 859 */ 860 static state_func_t 861 single_user(void) 862 { 863 pid_t pid, wpid; 864 int status; 865 sigset_t mask; 866 const char *shell; 867 char *argv[2]; 868 struct timeval tv, tn; 869 #ifdef SECURE 870 struct ttyent *typ; 871 struct passwd *pp; 872 static const char banner[] = 873 "Enter root password, or ^D to go multi-user\n"; 874 char *clear, *password; 875 #endif 876 #ifdef DEBUGSHELL 877 char altshell[128]; 878 #endif 879 880 if (Reboot) { 881 /* Instead of going single user, let's reboot the machine */ 882 BOOTTRACE("shutting down the system"); 883 sync(); 884 /* Run scripts after all processes have been terminated. */ 885 runfinal(); 886 if (reboot(howto) == -1) { 887 emergency("reboot(%#x) failed, %m", howto); 888 _exit(1); /* panic and reboot */ 889 } 890 warning("reboot(%#x) returned", howto); 891 _exit(0); /* panic as well */ 892 } 893 894 BOOTTRACE("going to single user mode"); 895 shell = get_shell(); 896 897 if ((pid = fork()) == 0) { 898 /* 899 * Start the single user session. 900 */ 901 open_console(); 902 903 #ifdef SECURE 904 /* 905 * Check the root password. 906 * We don't care if the console is 'on' by default; 907 * it's the only tty that can be 'off' and 'secure'. 908 */ 909 typ = getttynam("console"); 910 pp = getpwnam("root"); 911 if (typ && (typ->ty_status & TTY_SECURE) == 0 && 912 pp && *pp->pw_passwd) { 913 write_stderr(banner); 914 for (;;) { 915 clear = getpass("Password:"); 916 if (clear == NULL || *clear == '\0') 917 _exit(0); 918 password = crypt(clear, pp->pw_passwd); 919 explicit_bzero(clear, _PASSWORD_LEN); 920 if (password != NULL && 921 strcmp(password, pp->pw_passwd) == 0) 922 break; 923 warning("single-user login failed\n"); 924 } 925 } 926 endttyent(); 927 endpwent(); 928 #endif /* SECURE */ 929 930 #ifdef DEBUGSHELL 931 { 932 char *cp = altshell; 933 int num; 934 935 #define SHREQUEST "Enter full pathname of shell or RETURN for " 936 write_stderr(SHREQUEST); 937 write_stderr(shell); 938 write_stderr(": "); 939 while ((num = read(STDIN_FILENO, cp, 1)) != -1 && 940 num != 0 && *cp != '\n' && cp < &altshell[127]) 941 cp++; 942 *cp = '\0'; 943 if (altshell[0] != '\0') 944 shell = altshell; 945 } 946 #endif /* DEBUGSHELL */ 947 948 /* 949 * Unblock signals. 950 * We catch all the interesting ones, 951 * and those are reset to SIG_DFL on exec. 952 */ 953 sigemptyset(&mask); 954 sigprocmask(SIG_SETMASK, &mask, NULL); 955 956 /* 957 * Fire off a shell. 958 * If the default one doesn't work, try the Bourne shell. 959 */ 960 961 char name[] = "-sh"; 962 963 argv[0] = name; 964 argv[1] = NULL; 965 execv(shell, argv); 966 emergency("can't exec %s for single user: %m", shell); 967 execv(_PATH_BSHELL, argv); 968 emergency("can't exec %s for single user: %m", _PATH_BSHELL); 969 sleep(STALL_TIMEOUT); 970 _exit(1); 971 } 972 973 if (pid == -1) { 974 /* 975 * We are seriously hosed. Do our best. 976 */ 977 emergency("can't fork single-user shell, trying again"); 978 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 979 continue; 980 return (state_func_t) single_user; 981 } 982 983 requested_transition = 0; 984 do { 985 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 986 collect_child(wpid); 987 if (wpid == -1) { 988 if (errno == EINTR) 989 continue; 990 warning("wait for single-user shell failed: %m; restarting"); 991 return (state_func_t) single_user; 992 } 993 if (wpid == pid && WIFSTOPPED(status)) { 994 warning("init: shell stopped, restarting\n"); 995 kill(pid, SIGCONT); 996 wpid = -1; 997 } 998 } while (wpid != pid && !requested_transition); 999 1000 if (requested_transition) 1001 return (state_func_t) requested_transition; 1002 1003 if (!WIFEXITED(status)) { 1004 if (WTERMSIG(status) == SIGKILL) { 1005 /* 1006 * reboot(8) killed shell? 1007 */ 1008 warning("single user shell terminated."); 1009 gettimeofday(&tv, NULL); 1010 tn = tv; 1011 tv.tv_sec += STALL_TIMEOUT; 1012 while (tv.tv_sec > tn.tv_sec || (tv.tv_sec == 1013 tn.tv_sec && tv.tv_usec > tn.tv_usec)) { 1014 sleep(1); 1015 gettimeofday(&tn, NULL); 1016 } 1017 _exit(0); 1018 } else { 1019 warning("single user shell terminated, restarting"); 1020 return (state_func_t) single_user; 1021 } 1022 } 1023 1024 runcom_mode = FASTBOOT; 1025 return (state_func_t) runcom; 1026 } 1027 1028 /* 1029 * Run the system startup script. 1030 */ 1031 static state_func_t 1032 runcom(void) 1033 { 1034 state_func_t next_transition; 1035 1036 BOOTTRACE("/etc/rc starting..."); 1037 if ((next_transition = run_script(_PATH_RUNCOM)) != NULL) 1038 return next_transition; 1039 BOOTTRACE("/etc/rc finished"); 1040 1041 runcom_mode = AUTOBOOT; /* the default */ 1042 return (state_func_t) read_ttys; 1043 } 1044 1045 static void 1046 execute_script(char *argv[]) 1047 { 1048 struct sigaction sa; 1049 const char *shell, *script; 1050 int error; 1051 1052 bzero(&sa, sizeof(sa)); 1053 sigemptyset(&sa.sa_mask); 1054 sa.sa_handler = SIG_IGN; 1055 sigaction(SIGTSTP, &sa, NULL); 1056 sigaction(SIGHUP, &sa, NULL); 1057 1058 open_console(); 1059 1060 sigprocmask(SIG_SETMASK, &sa.sa_mask, NULL); 1061 #ifdef LOGIN_CAP 1062 setprocresources(RESOURCE_RC); 1063 #endif 1064 1065 /* 1066 * Try to directly execute the script first. If it 1067 * fails, try the old method of passing the script path 1068 * to sh(1). Don't complain if it fails because of 1069 * the missing execute bit. 1070 */ 1071 script = argv[1]; 1072 error = access(script, X_OK); 1073 if (error == 0) { 1074 execv(script, argv + 1); 1075 warning("can't directly exec %s: %m", script); 1076 } else if (errno != EACCES) { 1077 warning("can't access %s: %m", script); 1078 } 1079 1080 shell = get_shell(); 1081 execv(shell, argv); 1082 stall("can't exec %s for %s: %m", shell, script); 1083 } 1084 1085 /* 1086 * Execute binary, replacing init(8) as PID 1. 1087 */ 1088 static void 1089 replace_init(char *path) 1090 { 1091 char *argv[3]; 1092 char sh[] = "sh"; 1093 1094 argv[0] = sh; 1095 argv[1] = path; 1096 argv[2] = NULL; 1097 1098 execute_script(argv); 1099 } 1100 1101 /* 1102 * Run a shell script. 1103 * Returns 0 on success, otherwise the next transition to enter: 1104 * - single_user if fork/execv/waitpid failed, or if the script 1105 * terminated with a signal or exit code != 0. 1106 * - death_single if a SIGTERM was delivered to init(8). 1107 */ 1108 static state_func_t 1109 run_script(const char *script) 1110 { 1111 pid_t pid, wpid; 1112 int status; 1113 char *argv[4]; 1114 const char *shell; 1115 1116 shell = get_shell(); 1117 1118 if ((pid = fork()) == 0) { 1119 1120 char _sh[] = "sh"; 1121 char _autoboot[] = "autoboot"; 1122 1123 argv[0] = _sh; 1124 argv[1] = __DECONST(char *, script); 1125 argv[2] = runcom_mode == AUTOBOOT ? _autoboot : 0; 1126 argv[3] = NULL; 1127 1128 execute_script(argv); 1129 sleep(STALL_TIMEOUT); 1130 _exit(1); /* force single user mode */ 1131 } 1132 1133 if (pid == -1) { 1134 emergency("can't fork for %s on %s: %m", shell, script); 1135 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 1136 continue; 1137 sleep(STALL_TIMEOUT); 1138 return (state_func_t) single_user; 1139 } 1140 1141 /* 1142 * Copied from single_user(). This is a bit paranoid. 1143 */ 1144 requested_transition = 0; 1145 do { 1146 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 1147 collect_child(wpid); 1148 if (wpid == -1) { 1149 if (requested_transition == death_single || 1150 requested_transition == reroot) 1151 return (state_func_t) requested_transition; 1152 if (errno == EINTR) 1153 continue; 1154 warning("wait for %s on %s failed: %m; going to " 1155 "single user mode", shell, script); 1156 return (state_func_t) single_user; 1157 } 1158 if (wpid == pid && WIFSTOPPED(status)) { 1159 warning("init: %s on %s stopped, restarting\n", 1160 shell, script); 1161 kill(pid, SIGCONT); 1162 wpid = -1; 1163 } 1164 } while (wpid != pid); 1165 1166 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && 1167 requested_transition == catatonia) { 1168 /* /etc/rc executed /sbin/reboot; wait for the end quietly */ 1169 sigset_t s; 1170 1171 sigfillset(&s); 1172 for (;;) 1173 sigsuspend(&s); 1174 } 1175 1176 if (!WIFEXITED(status)) { 1177 warning("%s on %s terminated abnormally, going to single " 1178 "user mode", shell, script); 1179 return (state_func_t) single_user; 1180 } 1181 1182 if (WEXITSTATUS(status)) 1183 return (state_func_t) single_user; 1184 1185 return (state_func_t) 0; 1186 } 1187 1188 /* 1189 * Open the session database. 1190 * 1191 * NB: We could pass in the size here; is it necessary? 1192 */ 1193 static int 1194 start_session_db(void) 1195 { 1196 if (session_db && (*session_db->close)(session_db)) 1197 emergency("session database close: %m"); 1198 if ((session_db = dbopen(NULL, O_RDWR, 0, DB_HASH, NULL)) == NULL) { 1199 emergency("session database open: %m"); 1200 return (1); 1201 } 1202 return (0); 1203 1204 } 1205 1206 /* 1207 * Add a new login session. 1208 */ 1209 static void 1210 add_session(session_t *sp) 1211 { 1212 DBT key; 1213 DBT data; 1214 1215 key.data = &sp->se_process; 1216 key.size = sizeof sp->se_process; 1217 data.data = &sp; 1218 data.size = sizeof sp; 1219 1220 if ((*session_db->put)(session_db, &key, &data, 0)) 1221 emergency("insert %d: %m", sp->se_process); 1222 } 1223 1224 /* 1225 * Delete an old login session. 1226 */ 1227 static void 1228 del_session(session_t *sp) 1229 { 1230 DBT key; 1231 1232 key.data = &sp->se_process; 1233 key.size = sizeof sp->se_process; 1234 1235 if ((*session_db->del)(session_db, &key, 0)) 1236 emergency("delete %d: %m", sp->se_process); 1237 } 1238 1239 /* 1240 * Look up a login session by pid. 1241 */ 1242 static session_t * 1243 find_session(pid_t pid) 1244 { 1245 DBT key; 1246 DBT data; 1247 session_t *ret; 1248 1249 key.data = &pid; 1250 key.size = sizeof pid; 1251 if ((*session_db->get)(session_db, &key, &data, 0) != 0) 1252 return 0; 1253 bcopy(data.data, (char *)&ret, sizeof(ret)); 1254 return ret; 1255 } 1256 1257 /* 1258 * Construct an argument vector from a command line. 1259 */ 1260 static char ** 1261 construct_argv(char *command) 1262 { 1263 int argc = 0; 1264 char **argv = (char **) malloc(((strlen(command) + 1) / 2 + 1) 1265 * sizeof (char *)); 1266 1267 if ((argv[argc++] = strk(command)) == NULL) { 1268 free(argv); 1269 return (NULL); 1270 } 1271 while ((argv[argc++] = strk((char *) 0)) != NULL) 1272 continue; 1273 return argv; 1274 } 1275 1276 /* 1277 * Deallocate a session descriptor. 1278 */ 1279 static void 1280 free_session(session_t *sp) 1281 { 1282 free(sp->se_device); 1283 if (sp->se_getty) { 1284 free(sp->se_getty); 1285 free(sp->se_getty_argv_space); 1286 free(sp->se_getty_argv); 1287 } 1288 if (sp->se_window) { 1289 free(sp->se_window); 1290 free(sp->se_window_argv_space); 1291 free(sp->se_window_argv); 1292 } 1293 if (sp->se_type) 1294 free(sp->se_type); 1295 free(sp); 1296 } 1297 1298 /* 1299 * Allocate a new session descriptor. 1300 * Mark it SE_PRESENT. 1301 */ 1302 static session_t * 1303 new_session(session_t *sprev, struct ttyent *typ) 1304 { 1305 session_t *sp; 1306 1307 if ((typ->ty_status & TTY_ON) == 0 || 1308 typ->ty_name == 0 || 1309 typ->ty_getty == 0) 1310 return 0; 1311 1312 sp = (session_t *) calloc(1, sizeof (session_t)); 1313 1314 sp->se_flags |= SE_PRESENT; 1315 1316 if ((typ->ty_status & TTY_IFEXISTS) != 0) 1317 sp->se_flags |= SE_IFEXISTS; 1318 1319 if ((typ->ty_status & TTY_IFCONSOLE) != 0) 1320 sp->se_flags |= SE_IFCONSOLE; 1321 1322 if (asprintf(&sp->se_device, "%s%s", _PATH_DEV, typ->ty_name) < 0) 1323 err(1, "asprintf"); 1324 1325 if (setupargv(sp, typ) == 0) { 1326 free_session(sp); 1327 return (0); 1328 } 1329 1330 sp->se_next = 0; 1331 if (sprev == NULL) { 1332 sessions = sp; 1333 sp->se_prev = 0; 1334 } else { 1335 sprev->se_next = sp; 1336 sp->se_prev = sprev; 1337 } 1338 1339 return sp; 1340 } 1341 1342 /* 1343 * Calculate getty and if useful window argv vectors. 1344 */ 1345 static int 1346 setupargv(session_t *sp, struct ttyent *typ) 1347 { 1348 1349 if (sp->se_getty) { 1350 free(sp->se_getty); 1351 free(sp->se_getty_argv_space); 1352 free(sp->se_getty_argv); 1353 } 1354 if (asprintf(&sp->se_getty, "%s %s", typ->ty_getty, typ->ty_name) < 0) 1355 err(1, "asprintf"); 1356 sp->se_getty_argv_space = strdup(sp->se_getty); 1357 sp->se_getty_argv = construct_argv(sp->se_getty_argv_space); 1358 if (sp->se_getty_argv == NULL) { 1359 warning("can't parse getty for port %s", sp->se_device); 1360 free(sp->se_getty); 1361 free(sp->se_getty_argv_space); 1362 sp->se_getty = sp->se_getty_argv_space = 0; 1363 return (0); 1364 } 1365 if (sp->se_window) { 1366 free(sp->se_window); 1367 free(sp->se_window_argv_space); 1368 free(sp->se_window_argv); 1369 } 1370 sp->se_window = sp->se_window_argv_space = 0; 1371 sp->se_window_argv = 0; 1372 if (typ->ty_window) { 1373 sp->se_window = strdup(typ->ty_window); 1374 sp->se_window_argv_space = strdup(sp->se_window); 1375 sp->se_window_argv = construct_argv(sp->se_window_argv_space); 1376 if (sp->se_window_argv == NULL) { 1377 warning("can't parse window for port %s", 1378 sp->se_device); 1379 free(sp->se_window_argv_space); 1380 free(sp->se_window); 1381 sp->se_window = sp->se_window_argv_space = 0; 1382 return (0); 1383 } 1384 } 1385 if (sp->se_type) 1386 free(sp->se_type); 1387 sp->se_type = typ->ty_type ? strdup(typ->ty_type) : 0; 1388 return (1); 1389 } 1390 1391 /* 1392 * Walk the list of ttys and create sessions for each active line. 1393 */ 1394 static state_func_t 1395 read_ttys(void) 1396 { 1397 session_t *sp, *snext; 1398 struct ttyent *typ; 1399 1400 /* 1401 * Destroy any previous session state. 1402 * There shouldn't be any, but just in case... 1403 */ 1404 for (sp = sessions; sp; sp = snext) { 1405 snext = sp->se_next; 1406 free_session(sp); 1407 } 1408 sessions = 0; 1409 if (start_session_db()) 1410 return (state_func_t) single_user; 1411 1412 /* 1413 * Allocate a session entry for each active port. 1414 * Note that sp starts at 0. 1415 */ 1416 while ((typ = getttyent()) != NULL) 1417 if ((snext = new_session(sp, typ)) != NULL) 1418 sp = snext; 1419 1420 endttyent(); 1421 1422 return (state_func_t) multi_user; 1423 } 1424 1425 /* 1426 * Start a window system running. 1427 */ 1428 static void 1429 start_window_system(session_t *sp) 1430 { 1431 pid_t pid; 1432 sigset_t mask; 1433 char term[64], *env[2]; 1434 int status; 1435 1436 if ((pid = fork()) == -1) { 1437 emergency("can't fork for window system on port %s: %m", 1438 sp->se_device); 1439 /* hope that getty fails and we can try again */ 1440 return; 1441 } 1442 if (pid) { 1443 waitpid(-1, &status, 0); 1444 return; 1445 } 1446 1447 /* reparent window process to the init to not make a zombie on exit */ 1448 if ((pid = fork()) == -1) { 1449 emergency("can't fork for window system on port %s: %m", 1450 sp->se_device); 1451 _exit(1); 1452 } 1453 if (pid) 1454 _exit(0); 1455 1456 sigemptyset(&mask); 1457 sigprocmask(SIG_SETMASK, &mask, NULL); 1458 1459 if (setsid() < 0) 1460 emergency("setsid failed (window) %m"); 1461 1462 #ifdef LOGIN_CAP 1463 setprocresources(RESOURCE_WINDOW); 1464 #endif 1465 if (sp->se_type) { 1466 /* Don't use malloc after fork */ 1467 strcpy(term, "TERM="); 1468 strlcat(term, sp->se_type, sizeof(term)); 1469 env[0] = term; 1470 env[1] = NULL; 1471 } 1472 else 1473 env[0] = NULL; 1474 execve(sp->se_window_argv[0], sp->se_window_argv, env); 1475 stall("can't exec window system '%s' for port %s: %m", 1476 sp->se_window_argv[0], sp->se_device); 1477 _exit(1); 1478 } 1479 1480 /* 1481 * Start a login session running. 1482 */ 1483 static pid_t 1484 start_getty(session_t *sp) 1485 { 1486 pid_t pid; 1487 sigset_t mask; 1488 time_t current_time = time((time_t *) 0); 1489 int too_quick = 0; 1490 char term[64], *env[2]; 1491 1492 if (current_time >= sp->se_started && 1493 current_time - sp->se_started < GETTY_SPACING) { 1494 if (++sp->se_nspace > GETTY_NSPACE) { 1495 sp->se_nspace = 0; 1496 too_quick = 1; 1497 } 1498 } else 1499 sp->se_nspace = 0; 1500 1501 /* 1502 * fork(), not vfork() -- we can't afford to block. 1503 */ 1504 if ((pid = fork()) == -1) { 1505 emergency("can't fork for getty on port %s: %m", sp->se_device); 1506 return -1; 1507 } 1508 1509 if (pid) 1510 return pid; 1511 1512 if (too_quick) { 1513 warning("getty repeating too quickly on port %s, sleeping %d secs", 1514 sp->se_device, GETTY_SLEEP); 1515 sleep((unsigned) GETTY_SLEEP); 1516 } 1517 1518 if (sp->se_window) { 1519 start_window_system(sp); 1520 sleep(WINDOW_WAIT); 1521 } 1522 1523 sigemptyset(&mask); 1524 sigprocmask(SIG_SETMASK, &mask, NULL); 1525 1526 #ifdef LOGIN_CAP 1527 setprocresources(RESOURCE_GETTY); 1528 #endif 1529 if (sp->se_type) { 1530 /* Don't use malloc after fork */ 1531 strcpy(term, "TERM="); 1532 strlcat(term, sp->se_type, sizeof(term)); 1533 env[0] = term; 1534 env[1] = NULL; 1535 } else 1536 env[0] = NULL; 1537 execve(sp->se_getty_argv[0], sp->se_getty_argv, env); 1538 stall("can't exec getty '%s' for port %s: %m", 1539 sp->se_getty_argv[0], sp->se_device); 1540 _exit(1); 1541 } 1542 1543 /* 1544 * Return 1 if the session is defined as "onifexists" 1545 * or "onifconsole" and the device node does not exist. 1546 */ 1547 static int 1548 session_has_no_tty(session_t *sp) 1549 { 1550 int fd; 1551 1552 if ((sp->se_flags & SE_IFEXISTS) == 0 && 1553 (sp->se_flags & SE_IFCONSOLE) == 0) 1554 return (0); 1555 1556 fd = open(sp->se_device, O_RDONLY | O_NONBLOCK, 0); 1557 if (fd < 0) { 1558 if (errno == ENOENT) 1559 return (1); 1560 return (0); 1561 } 1562 1563 close(fd); 1564 return (0); 1565 } 1566 1567 /* 1568 * Collect exit status for a child. 1569 * If an exiting login, start a new login running. 1570 */ 1571 static void 1572 collect_child(pid_t pid) 1573 { 1574 session_t *sp, *sprev, *snext; 1575 1576 if (! sessions) 1577 return; 1578 1579 if (! (sp = find_session(pid))) 1580 return; 1581 1582 del_session(sp); 1583 sp->se_process = 0; 1584 1585 if (sp->se_flags & SE_SHUTDOWN || 1586 session_has_no_tty(sp)) { 1587 if ((sprev = sp->se_prev) != NULL) 1588 sprev->se_next = sp->se_next; 1589 else 1590 sessions = sp->se_next; 1591 if ((snext = sp->se_next) != NULL) 1592 snext->se_prev = sp->se_prev; 1593 free_session(sp); 1594 return; 1595 } 1596 1597 if ((pid = start_getty(sp)) == -1) { 1598 /* serious trouble */ 1599 requested_transition = clean_ttys; 1600 return; 1601 } 1602 1603 sp->se_process = pid; 1604 sp->se_started = time((time_t *) 0); 1605 add_session(sp); 1606 } 1607 1608 static const char * 1609 get_current_state(void) 1610 { 1611 1612 if (current_state == single_user) 1613 return ("single-user"); 1614 if (current_state == runcom) 1615 return ("runcom"); 1616 if (current_state == read_ttys) 1617 return ("read-ttys"); 1618 if (current_state == multi_user) 1619 return ("multi-user"); 1620 if (current_state == clean_ttys) 1621 return ("clean-ttys"); 1622 if (current_state == catatonia) 1623 return ("catatonia"); 1624 if (current_state == death) 1625 return ("death"); 1626 if (current_state == death_single) 1627 return ("death-single"); 1628 return ("unknown"); 1629 } 1630 1631 static void 1632 boottrace_transition(int sig) 1633 { 1634 const char *action; 1635 1636 switch (sig) { 1637 case SIGUSR2: 1638 action = "halt & poweroff"; 1639 break; 1640 case SIGUSR1: 1641 action = "halt"; 1642 break; 1643 case SIGINT: 1644 action = "reboot"; 1645 break; 1646 case SIGWINCH: 1647 action = "powercycle"; 1648 break; 1649 case SIGTERM: 1650 action = Reboot ? "reboot" : "single-user"; 1651 break; 1652 default: 1653 BOOTTRACE("signal %d from %s", sig, get_current_state()); 1654 return; 1655 } 1656 1657 /* Trace the shutdown reason. */ 1658 SHUTTRACE("%s from %s", action, get_current_state()); 1659 } 1660 1661 /* 1662 * Catch a signal and request a state transition. 1663 */ 1664 static void 1665 transition_handler(int sig) 1666 { 1667 1668 boottrace_transition(sig); 1669 switch (sig) { 1670 case SIGHUP: 1671 if (current_state == read_ttys || current_state == multi_user || 1672 current_state == clean_ttys || current_state == catatonia) 1673 requested_transition = clean_ttys; 1674 break; 1675 case SIGUSR2: 1676 howto = RB_POWEROFF; 1677 case SIGUSR1: 1678 howto |= RB_HALT; 1679 case SIGWINCH: 1680 case SIGINT: 1681 if (sig == SIGWINCH) 1682 howto |= RB_POWERCYCLE; 1683 Reboot = TRUE; 1684 case SIGTERM: 1685 if (current_state == read_ttys || current_state == multi_user || 1686 current_state == clean_ttys || current_state == catatonia) 1687 requested_transition = death; 1688 else 1689 requested_transition = death_single; 1690 break; 1691 case SIGTSTP: 1692 if (current_state == runcom || current_state == read_ttys || 1693 current_state == clean_ttys || 1694 current_state == multi_user || current_state == catatonia) 1695 requested_transition = catatonia; 1696 break; 1697 case SIGEMT: 1698 requested_transition = reroot; 1699 break; 1700 default: 1701 requested_transition = 0; 1702 break; 1703 } 1704 } 1705 1706 /* 1707 * Take the system multiuser. 1708 */ 1709 static state_func_t 1710 multi_user(void) 1711 { 1712 static bool inmultiuser = false; 1713 pid_t pid; 1714 session_t *sp; 1715 1716 requested_transition = 0; 1717 1718 /* 1719 * If the administrator has not set the security level to -1 1720 * to indicate that the kernel should not run multiuser in secure 1721 * mode, and the run script has not set a higher level of security 1722 * than level 1, then put the kernel into secure mode. 1723 */ 1724 if (getsecuritylevel() == 0) 1725 setsecuritylevel(1); 1726 1727 for (sp = sessions; sp; sp = sp->se_next) { 1728 if (sp->se_process) 1729 continue; 1730 if (session_has_no_tty(sp)) 1731 continue; 1732 if ((pid = start_getty(sp)) == -1) { 1733 /* serious trouble */ 1734 requested_transition = clean_ttys; 1735 break; 1736 } 1737 sp->se_process = pid; 1738 sp->se_started = time((time_t *) 0); 1739 add_session(sp); 1740 } 1741 1742 if (requested_transition == 0 && !inmultiuser) { 1743 inmultiuser = true; 1744 /* This marks the change from boot-time tracing to run-time. */ 1745 RUNTRACE("multi-user start"); 1746 } 1747 while (!requested_transition) 1748 if ((pid = waitpid(-1, (int *) 0, 0)) != -1) 1749 collect_child(pid); 1750 1751 return (state_func_t) requested_transition; 1752 } 1753 1754 /* 1755 * This is an (n*2)+(n^2) algorithm. We hope it isn't run often... 1756 */ 1757 static state_func_t 1758 clean_ttys(void) 1759 { 1760 session_t *sp, *sprev; 1761 struct ttyent *typ; 1762 int devlen; 1763 char *old_getty, *old_window, *old_type; 1764 1765 /* 1766 * mark all sessions for death, (!SE_PRESENT) 1767 * as we find or create new ones they'll be marked as keepers, 1768 * we'll later nuke all the ones not found in /etc/ttys 1769 */ 1770 for (sp = sessions; sp != NULL; sp = sp->se_next) 1771 sp->se_flags &= ~SE_PRESENT; 1772 1773 devlen = sizeof(_PATH_DEV) - 1; 1774 while ((typ = getttyent()) != NULL) { 1775 for (sprev = 0, sp = sessions; sp; sprev = sp, sp = sp->se_next) 1776 if (strcmp(typ->ty_name, sp->se_device + devlen) == 0) 1777 break; 1778 1779 if (sp) { 1780 /* we want this one to live */ 1781 sp->se_flags |= SE_PRESENT; 1782 if ((typ->ty_status & TTY_ON) == 0 || 1783 typ->ty_getty == 0) { 1784 sp->se_flags |= SE_SHUTDOWN; 1785 kill(sp->se_process, SIGHUP); 1786 continue; 1787 } 1788 sp->se_flags &= ~SE_SHUTDOWN; 1789 old_getty = sp->se_getty ? strdup(sp->se_getty) : 0; 1790 old_window = sp->se_window ? strdup(sp->se_window) : 0; 1791 old_type = sp->se_type ? strdup(sp->se_type) : 0; 1792 if (setupargv(sp, typ) == 0) { 1793 warning("can't parse getty for port %s", 1794 sp->se_device); 1795 sp->se_flags |= SE_SHUTDOWN; 1796 kill(sp->se_process, SIGHUP); 1797 } 1798 else if ( !old_getty 1799 || (!old_type && sp->se_type) 1800 || (old_type && !sp->se_type) 1801 || (!old_window && sp->se_window) 1802 || (old_window && !sp->se_window) 1803 || (strcmp(old_getty, sp->se_getty) != 0) 1804 || (old_window && strcmp(old_window, sp->se_window) != 0) 1805 || (old_type && strcmp(old_type, sp->se_type) != 0) 1806 ) { 1807 /* Don't set SE_SHUTDOWN here */ 1808 sp->se_nspace = 0; 1809 sp->se_started = 0; 1810 kill(sp->se_process, SIGHUP); 1811 } 1812 if (old_getty) 1813 free(old_getty); 1814 if (old_window) 1815 free(old_window); 1816 if (old_type) 1817 free(old_type); 1818 continue; 1819 } 1820 1821 new_session(sprev, typ); 1822 } 1823 1824 endttyent(); 1825 1826 /* 1827 * sweep through and kill all deleted sessions 1828 * ones who's /etc/ttys line was deleted (SE_PRESENT unset) 1829 */ 1830 for (sp = sessions; sp != NULL; sp = sp->se_next) { 1831 if ((sp->se_flags & SE_PRESENT) == 0) { 1832 sp->se_flags |= SE_SHUTDOWN; 1833 kill(sp->se_process, SIGHUP); 1834 } 1835 } 1836 1837 return (state_func_t) multi_user; 1838 } 1839 1840 /* 1841 * Block further logins. 1842 */ 1843 static state_func_t 1844 catatonia(void) 1845 { 1846 session_t *sp; 1847 1848 for (sp = sessions; sp; sp = sp->se_next) 1849 sp->se_flags |= SE_SHUTDOWN; 1850 1851 return (state_func_t) multi_user; 1852 } 1853 1854 /* 1855 * Note SIGALRM. 1856 */ 1857 static void 1858 alrm_handler(int sig) 1859 { 1860 1861 (void)sig; 1862 clang = 1; 1863 } 1864 1865 /* 1866 * Bring the system down to single user. 1867 */ 1868 static state_func_t 1869 death(void) 1870 { 1871 int block, blocked; 1872 size_t len; 1873 1874 /* Temporarily block suspend. */ 1875 len = sizeof(blocked); 1876 block = 1; 1877 if (sysctlbyname("kern.suspend_blocked", &blocked, &len, 1878 &block, sizeof(block)) == -1) 1879 blocked = 0; 1880 1881 /* 1882 * Also revoke the TTY here. Because runshutdown() may reopen 1883 * the TTY whose getty we're killing here, there is no guarantee 1884 * runshutdown() will perform the initial open() call, causing 1885 * the terminal attributes to be misconfigured. 1886 */ 1887 revoke_ttys(); 1888 1889 /* Try to run the rc.shutdown script within a period of time */ 1890 runshutdown(); 1891 1892 /* Unblock suspend if we blocked it. */ 1893 if (!blocked) 1894 sysctlbyname("kern.suspend_blocked", NULL, NULL, 1895 &blocked, sizeof(blocked)); 1896 1897 return (state_func_t) death_single; 1898 } 1899 1900 /* 1901 * Do what is necessary to reinitialize single user mode or reboot 1902 * from an incomplete state. 1903 */ 1904 static state_func_t 1905 death_single(void) 1906 { 1907 int i; 1908 pid_t pid; 1909 static const int death_sigs[2] = { SIGTERM, SIGKILL }; 1910 1911 revoke(_PATH_CONSOLE); 1912 1913 BOOTTRACE("start killing user processes"); 1914 for (i = 0; i < 2; ++i) { 1915 if (kill(-1, death_sigs[i]) == -1 && errno == ESRCH) 1916 return (state_func_t) single_user; 1917 1918 clang = 0; 1919 alarm(DEATH_WATCH); 1920 do 1921 if ((pid = waitpid(-1, (int *)0, 0)) != -1) 1922 collect_child(pid); 1923 while (clang == 0 && errno != ECHILD); 1924 1925 if (errno == ECHILD) 1926 return (state_func_t) single_user; 1927 } 1928 1929 warning("some processes would not die; ps axl advised"); 1930 1931 return (state_func_t) single_user; 1932 } 1933 1934 static void 1935 revoke_ttys(void) 1936 { 1937 session_t *sp; 1938 1939 for (sp = sessions; sp; sp = sp->se_next) { 1940 sp->se_flags |= SE_SHUTDOWN; 1941 kill(sp->se_process, SIGHUP); 1942 revoke(sp->se_device); 1943 } 1944 } 1945 1946 /* 1947 * Run the system shutdown script. 1948 * 1949 * Exit codes: XXX I should document more 1950 * -2 shutdown script terminated abnormally 1951 * -1 fatal error - can't run script 1952 * 0 good. 1953 * >0 some error (exit code) 1954 */ 1955 static int 1956 runshutdown(void) 1957 { 1958 pid_t pid, wpid; 1959 int status; 1960 int shutdowntimeout; 1961 size_t len; 1962 char *argv[4]; 1963 struct stat sb; 1964 1965 BOOTTRACE("init(8): start rc.shutdown"); 1966 1967 /* 1968 * rc.shutdown is optional, so to prevent any unnecessary 1969 * complaints from the shell we simply don't run it if the 1970 * file does not exist. If the stat() here fails for other 1971 * reasons, we'll let the shell complain. 1972 */ 1973 if (stat(_PATH_RUNDOWN, &sb) == -1 && errno == ENOENT) 1974 return 0; 1975 1976 if ((pid = fork()) == 0) { 1977 char _sh[] = "sh"; 1978 char _reboot[] = "reboot"; 1979 char _single[] = "single"; 1980 char _path_rundown[] = _PATH_RUNDOWN; 1981 1982 argv[0] = _sh; 1983 argv[1] = _path_rundown; 1984 argv[2] = Reboot ? _reboot : _single; 1985 argv[3] = NULL; 1986 1987 execute_script(argv); 1988 _exit(1); /* force single user mode */ 1989 } 1990 1991 if (pid == -1) { 1992 emergency("can't fork for %s: %m", _PATH_RUNDOWN); 1993 while (waitpid(-1, (int *) 0, WNOHANG) > 0) 1994 continue; 1995 sleep(STALL_TIMEOUT); 1996 return -1; 1997 } 1998 1999 len = sizeof(shutdowntimeout); 2000 if (sysctlbyname("kern.init_shutdown_timeout", &shutdowntimeout, &len, 2001 NULL, 0) == -1 || shutdowntimeout < 2) 2002 shutdowntimeout = DEATH_SCRIPT; 2003 alarm(shutdowntimeout); 2004 clang = 0; 2005 /* 2006 * Copied from single_user(). This is a bit paranoid. 2007 * Use the same ALRM handler. 2008 */ 2009 do { 2010 if ((wpid = waitpid(-1, &status, WUNTRACED)) != -1) 2011 collect_child(wpid); 2012 if (clang == 1) { 2013 /* we were waiting for the sub-shell */ 2014 kill(wpid, SIGTERM); 2015 warning("timeout expired for %s: %m; going to " 2016 "single user mode", _PATH_RUNDOWN); 2017 BOOTTRACE("rc.shutdown's %d sec timeout expired", 2018 shutdowntimeout); 2019 return -1; 2020 } 2021 if (wpid == -1) { 2022 if (errno == EINTR) 2023 continue; 2024 warning("wait for %s failed: %m; going to " 2025 "single user mode", _PATH_RUNDOWN); 2026 return -1; 2027 } 2028 if (wpid == pid && WIFSTOPPED(status)) { 2029 warning("init: %s stopped, restarting\n", 2030 _PATH_RUNDOWN); 2031 kill(pid, SIGCONT); 2032 wpid = -1; 2033 } 2034 } while (wpid != pid && !clang); 2035 2036 /* Turn off the alarm */ 2037 alarm(0); 2038 2039 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGTERM && 2040 requested_transition == catatonia) { 2041 /* 2042 * /etc/rc.shutdown executed /sbin/reboot; 2043 * wait for the end quietly 2044 */ 2045 sigset_t s; 2046 2047 sigfillset(&s); 2048 for (;;) 2049 sigsuspend(&s); 2050 } 2051 2052 if (!WIFEXITED(status)) { 2053 warning("%s terminated abnormally, going to " 2054 "single user mode", _PATH_RUNDOWN); 2055 return -2; 2056 } 2057 2058 if ((status = WEXITSTATUS(status)) != 0) 2059 warning("%s returned status %d", _PATH_RUNDOWN, status); 2060 2061 return status; 2062 } 2063 2064 static char * 2065 strk(char *p) 2066 { 2067 static char *t; 2068 char *q; 2069 int c; 2070 2071 if (p) 2072 t = p; 2073 if (!t) 2074 return 0; 2075 2076 c = *t; 2077 while (c == ' ' || c == '\t' ) 2078 c = *++t; 2079 if (!c) { 2080 t = 0; 2081 return 0; 2082 } 2083 q = t; 2084 if (c == '\'') { 2085 c = *++t; 2086 q = t; 2087 while (c && c != '\'') 2088 c = *++t; 2089 if (!c) /* unterminated string */ 2090 q = t = 0; 2091 else 2092 *t++ = 0; 2093 } else { 2094 while (c && c != ' ' && c != '\t' ) 2095 c = *++t; 2096 *t++ = 0; 2097 if (!c) 2098 t = 0; 2099 } 2100 return q; 2101 } 2102 2103 #ifdef LOGIN_CAP 2104 static void 2105 setprocresources(const char *cname) 2106 { 2107 login_cap_t *lc; 2108 if ((lc = login_getclassbyname(cname, NULL)) != NULL) { 2109 setusercontext(lc, (struct passwd*)NULL, 0, 2110 LOGIN_SETENV | 2111 LOGIN_SETPRIORITY | LOGIN_SETRESOURCES | 2112 LOGIN_SETLOGINCLASS | LOGIN_SETCPUMASK); 2113 login_close(lc); 2114 } 2115 } 2116 #endif 2117 2118 /* 2119 * Run /etc/rc.final to execute scripts after all user processes have been 2120 * terminated. 2121 */ 2122 static void 2123 runfinal(void) 2124 { 2125 struct stat sb; 2126 pid_t other_pid, pid; 2127 sigset_t mask; 2128 2129 /* Avoid any surprises. */ 2130 alarm(0); 2131 2132 /* rc.final is optional. */ 2133 if (stat(_PATH_RUNFINAL, &sb) == -1 && errno == ENOENT) 2134 return; 2135 if (access(_PATH_RUNFINAL, X_OK) != 0) { 2136 warning("%s exists, but not executable", _PATH_RUNFINAL); 2137 return; 2138 } 2139 2140 pid = fork(); 2141 if (pid == 0) { 2142 /* 2143 * Reopen stdin/stdout/stderr so that scripts can write to 2144 * console. 2145 */ 2146 close(0); 2147 open(_PATH_DEVNULL, O_RDONLY); 2148 close(1); 2149 close(2); 2150 open_console(); 2151 dup2(1, 2); 2152 sigemptyset(&mask); 2153 sigprocmask(SIG_SETMASK, &mask, NULL); 2154 signal(SIGCHLD, SIG_DFL); 2155 execl(_PATH_RUNFINAL, _PATH_RUNFINAL, NULL); 2156 perror("execl(" _PATH_RUNFINAL ") failed"); 2157 exit(1); 2158 } 2159 2160 /* Wait for rc.final script to exit */ 2161 while ((other_pid = waitpid(-1, NULL, 0)) != pid && other_pid > 0) { 2162 continue; 2163 } 2164 } 2165